Systems are known that electrolyze water containing alkali salts to produce acidic electrolyzed water and alkaline electrolyzed water. Acidic electrolyzed water, which typically has a pH between about 2.0 and about 3.5, generally comprises a disinfectant that is increasingly used in a variety of sanitizing applications including in the medical, agricultural and food processing industries and in other institutional environments. The alkaline or basic electrolyzed water also has a disinfecting as well as a detergent effect and is useful in cleaning oil and grease stains. Sodium chloride is commonly used as the alkali salt that is dissolved in the water because it produces acids and bases that are environmentally friendly, potent and low in cost.
Certain commercially available water electrolyzing systems are assembled “dry,” which can lead to wrinkling of the ion selective membrane(s) utilized with the systems. When present, the wrinkled membrane(s) causes increased electrical resistance in the electrolytic production of acidic electrolyzed water and alkaline electrolyzed water. In order to maintain production output for the system, the operator must increase voltage to maintain the electrical current at the increased resistance.
Another concern of using certain commercially available water electrolyzing systems arises from the pH of the acidic electrolyzed water, typically from about pH 2 to about pH 3.5. The acidic electrolyzed water at the typical pH range tends to limit the concentration of the disinfectant in the acidic electrolyzed water. Operating a certain commercially available water electrolyzing system supplied with softened water that was initially reasonably “hard,” e.g., contained a reasonably high concentration of soluble calcium and/or magnesium, tends to provide the system with a buffered water supply, which can sometimes provide a beneficial pH for producing acidic electrolyzed water having an optimum concentration of disinfectant. However, the beneficial results generally are not achieved if the water is initially reasonably soft.
Users would prefer to have a system that produces aqueous acidic solution and aqueous alkaline solution that requires the least amount of energy input (i.e., direct current voltage) into the system. In order to lower the energy input, the system should attempt to minimize the electrical resistance while maintaining adequate electrical current to produce the desired amount or concentration of aqueous acidic solution and/or aqueous alkaline solution.